It's a really good manga.
Yashiro (the female MC, who is insecure of her legs to the point of becoming a recurrent joke) accidentally curses herself after summoning the legendary spirit "Hanako-chan of the toilet" (which in this story is a boy and the other MC) to make him grant her her wish of getting a boyfriend. To undo her curse, Yashiro agrees to become Hanako-kun's servant and help him to deal with all sorts of spirits that cause troubles in their school, all while she cleans the bathrooms where Hanako resides and tries to find more about Hanako's mysterious past. Shortly after Yashiro makes a deal with Hanako, Kou, an exorcist in training, finds Hanako and tries to purge him, but since he's too much of a
good boy to actually do it he decides to join Hanako and Yashiro's mischief, at first to keep an eye on Hanako and later because they became good friends. Things happen, spirits big and small that suddenly became violent are dealt with, Hanako decides to start investigating with the help of Yashiro and Kou why is it happening, his twin brother Tsukasa appears a couple of times to give him horrific PTSD and cause mischief for lulz, a smug trap ghost appears and Kou
falls in love with
befriends him and makes Kou question
if purging ghosts is really a good thing, more characters appear, more cute, silly and sad things happen, etc. It's still ongoing and a lot of stuff happens, but this is an overall summary of it's beginning.